278580 divided by 21 
We're looking to find how many times 21 goes into 278580.

Let's proceed to step 1:
If we divide 2 by 21, we get 0 and a remainder of 2.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 2, we end up with 2.
Include the next digit (7) from the dividend after 2, then repeat: 27 / 21

On to step 2:
If we divide 27 by 21, we get 1 and a remainder of 6.
The next digit of our result is 1. 
Result so far: 1.0
If we take 21 away from 27, we end up with 6.
Include the next digit (8) from the dividend after 6, then repeat: 68 / 21

Going ahead to step 3:
21 goes into 68 3 times with a remainder of 5.
Put 3 as the next digit of the answer. 
Result so far: 13.0
The remainder is 5 after subtracting 63 from 68.
Take the next digit (5) from the dividend and append it to 5, then repeat: 55 / 21

On to step 4:
21 can be fit into 55 2 times, resulting in a remainder of 13.
The next digit of our result is 2. 
Result so far: 132.0
If we take 42 away from 55, we end up with 13.
Append the next digit (8) from the dividend to 13 and continue with: 138 / 21

Let's proceed to step 5:
21 goes into 138 6 times with a remainder of 12.
Use 6 as the next digit of our solution. 
Result so far: 1326.0
If we take 126 away from 138, we end up with 12.
Bring next digit (0) of the dividend behind the 12 and repeat the process: 120 / 21

Moving on to step 6:
120 divided by 21 is 5 with a remainder of 15.
Record the quotient 5 as the next digit in the result. 
Result so far: 13265.0
Subtract 105 from 120 to get 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

On to step 7:
21 can be fit into 150 7 times, resulting in a remainder of 3.
Write down 7 as next digit of the result. 
Result so far: 13265.7
If we subtract 147 from 150, we get 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Going ahead to step 8:
The number 21 fits into 30 1 times, leaving a remainder of 9.
Put 1 as the next digit of the answer. 
Result so far: 13265.71
If we subtract 21 from 30, we get 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Advancing to step 9:
If we divide 90 by 21, we get 4 and a remainder of 6.
The number 4 becomes the next digit in our result. 
Result so far: 13265.714
If we take 84 away from 90, we end up with 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

On to step 10:
60 divided by 21 is 2 with a remainder of 18.
The next digit of our result is 2. 
Result so far: 13265.7142
Subtracting 42 from 60 leaves us with 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

Advancing to step 11:
If we divide 180 by 21, we get 8 and a remainder of 12.
The next digit of our result is 8. 
Result so far: 13265.71428
If we take 168 away from 180, we end up with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Going ahead to step 12:
The number 21 fits into 120 5 times, leaving a remainder of 15.
Use 5 as the next digit of our solution. 
Result so far: 13265.714285
Deduct 105 from 120 and we're left with 15.
Since there are no more digits in the dividend, we add a zero to the remainder making it 150, and continue the process.

On to step 13:
When dividing 150 by 21, we get 7 with a remainder of 3.
Put 7 as the next digit of the answer. 
Result so far: 13265.7142857
If we subtract 147 from 150, we get 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

On to step 14:
21 can be fit into 30 1 times, resulting in a remainder of 9.
The number 1 becomes the next digit in our result. 
Result so far: 13265.71428571
If we take 21 away from 30, we end up with 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

The quotient of the division is 13265.71428571, and the remainder is 9e-09.